Soundproof shield



f o .Mm gw @eine "rss n Jl/'ALTER A.l SHEWHART, OF BROOKLYN, NEW YORK, ASSIGNOR TO 'WESTERN ELEC- TRIO COMPANY, INCORORATED, 0F NEW YORK, N. Y., A CORPORATON OF NEVI YORK.

Specification of Letters Patent.

SOUNDPROOE SHEELD.

Patented Jan. ill,

Application filed DecemberV 26, '1919. Serial No. 347,414.

To all 'LU/10m t may concern Be it known that I, iVm/run ."i. Sriniv- HART, a citizen of the `United States, residing at Brooklyn, in the county ot Kings and State of New York, have invented certain new and useful Improvements in Soundproof Shields, of which the following is a full, clear, concise, and exact description.

This invention relates to sound-proof shields tor telephone receiving instruments.

Shields tor use in sound-proofing telephone instruments of the `type used in head sets have heretofore existed in two general forms, neither of which has proven sutiiciently effective for employment in situations where outside noises tend to interfere with the use of the telephone instruments. Une of these forms has comprised a cup ol rubber in which the receiver was mounted. the walls ot the cup being relatively thin and presenting its edge to the head ot the wearer in a comparatively perpendicular position. This type of cup has proven wholly in'etiective for use in such trying situations as are found in airplane work where engine and wind noises are extremely hard to overcome. This has been due both to the inadequately thick walls of the cup member and to the unsubstantial, relatively narrow and correspondingly ineffective seal provided between the edge of the cup and the operators head,

' which failed to prevent extraneous noises from reaching the interior of the shield. The other' form has consisted of a comparatively thick-walled cup member i'ormed ot soft rubber and which also presented its edge to the head of the wearer in a coinparatively perpendicular relation thereto. This form, while providing' a greater degree of effectiveness than that of the thin-,walled cup previously referred to, was still' inadequate for the purpose in that the blunt and comparatively resistant edge of the cup would not yield or collapse to the required extent to faithfully follow the contour of the wearers head and thereby provide an elective seal. lt is the object ci they presentl invention to provide a soundproo't' shield in which the objections referred to are over-- come and which will provide an efficient sound-excluding seal with the head of the wearer. M

The invention consists in the provision o a cup member formedof sott rubber having a Haring and thinly tapering feather edge which, asvhas been repeatedly demonstrated in'practice, will provide a 'wide and etlective seal when pressed to the head of the operator. The invention also consists in' the provision ot a shield cup member tormed'ot relatively thick sponge rubber having its edge formed to tit theirregular contour of an operators head, and the use ot' this form ot cup in combination with the cup having the thinly tapering edge.

ln the drawings, Figure l is a view in perspective ot a telephone head set including soundproot receiver' shields embodying the invention; and Fig. 2 is an enlarged view partly in elevation, and partly in section, ot' one ot the sound-proof devices shown in Fig. l.

'ln the drawing, a cap member l is shown to which are attached elastic receiver supporting bands 2 and S which wholly encircle the head of the operator and cross each other siibstantially at right angles adjacent the operators ears and support seats 4 to which the receivers are attached.

ln order to shield the receivers from the eiilect of' extraneous noises a cup member 5 is provided which is preferably formed ot'` soft rubber, this material. having as a characteristic the power of preventing the passage 'therethrough ot sounds of low trequency, such as engine noises or the roaring sound of rushing wind-in airplane work. n important 'feature of the invention resides iu the thin feather er ge G with which the cup member is provided. the thinly tapering edge having a. widely flared forma4 tion which produces a wide area. oi contact between the fiat under surface ot' the edge and the head o? the operator. The thin :feather edge referred to yields readily under pressure and is easily collapsed to bring about a close contact of the thin edge with, every portion ot thc irregular contour oit' the surface to which the cup is pressed. Not is a. close Contact secured., but a sealing 'er olf suostantial width is achieved that very eti'ective in excluding noise.

"llo additionally insure the exclusion ot extraneous noises from the receiver l may provide the inner' cnp'meniber 8, preferably formed ot thick sponge rubber and having its edge formed to engage the operators head in a substantially perpendicular relation, as indicated in Fig. 2. The edge of the cup member 8 is formed to t the contour lil@ of the wearers head and for that purpose is provided with a` depression 9 designed to fit the projecting posterior portion of the operator-s jaw underneath the ear.

It will be seen that in addition to the sea-l provided by the contact of the two cup members with the operators head, the spaced apart relation oi the edges of the cup members forms an air chamberlO which itself tends to obstruct the passage of outside noises into the interior of the protecting' shield.

What is claimed is:

l. A soundprooi shield lor a telephone receiver consisting of a cup member formed of soft rubbei` and having a thin feather edge.

2. A sound-proof shield for a telephone receiver consisting of a thick-walled cup member formed of soft rubber and having a thinly tapering feather edge.

3. A sound-proof shield for telephone receivers consisting of a eup member formed of soft rubber and having a thinly tapering` widely flaring edge.

4. A sound-proof shield for telephone receivers consisting of an inner cup member my name formed or' soft rubber, and

an outer cup member formed of soft rubber and having a thin feather edge spaced from the edge of 6. A sound-proof shield for a telephone receiver consisting of an inner cup member formed of sponge rubber having its edge presented perpendieularly to and formed to [it the contour of the operators head, and an outer cup member formed of soit rubber' and having a thinly tapering widely Haring edge spaced from the edge ot said inner cup member and presenting a flat surface to the head ofthe wearer.

ln Witness whereoi, I hereunto subscribe this 23rd day of December, A. D..

l.VALTER A. SHEX lvHART. 

